1. Field of the Invention
The invention relates to an operating device for a flush operating knob with a locking device for the axial locking and unlocking of the operating knob that is extendable under spring load by means of a link guide, especially for the rotary switch of an automobile.
2. Description of the Related Art
It is common to flush-mount rotary knobs, such as those for the adjustment of brightness of lighting devices, in the instrument panel, and to release them from their home position by means of a simple push of the knob in order to activate the operating knob. The knob is then flush again by simply pushing it in, and locked in this position in order to hamper any unintentional activation and adjustment.
Generally, such devices, such as those according to DE 4330502 A, are provided with a stationary link component, in the cardioid of which a laterally traveling link pin, which is connected to the spring-loaded operating knob, engages in such a way that the axial position of the operating knob changes cycles by means of simply pressing between two different stroke positions. All stops and guides are embodied on the body, which appropriately must be designed in a complex and stable manner.